Container carriers



R A. MULLER CONTAINER CARRI May 27, 1969 ERS iors

Sheet Filed Feb. 24, 1967 INVENTOR fink/Am A. MILLER u j m 1 ATTORNEYS? May 27, 1969 R. A. MILLER CONTAINER CARRIERS INVENTOR.

Rwy/m0 A. MILLER v AT ORNEY5 ay 27, 1969 R. A. MILLER CONTAINER CARRIERS Sheet 3 of 8 Filed Feb. 24, 1967- INVENTOR. R MIMI? 1 Ml 5/2 A TTDR NE Y5 R E L I 7 M A R CONTAINER CARRIERS Filed Feb. 24, 1967 Illlllll'l INVENTOR. Rim/m A, M/ZLER ATTORNEYS Sheet 5 May 27, 1969 R. A. MILLER CONTAINER CARRIERS Filed Feb. 24, 1967 y 1969 R. A. MILLER CONTAINER CARRIERS Filed Feb. 24, 1967 g of 8 Sheet 11v VEN TOR. Alchmxa A. Mm El A T TO RNEYS NQ @Y Br WWMW y 1969 R. A. MILLER CONTAINER CARRIERS Sheet Filed Feb. 24, 1967 INVENTOR. a/MR0 A. M/LLEA ATTORA/fYJ Filed Feb. 24, 1967 Sheet INVENTOR. IF/cMRD A, MILLER A OR NEKS' dumping;

3,446,378 CONTAINER CARRIERS Richard A. Miller, Easton, Pa, assignor to Easton Car & Construction Company, Easton, Pa., a corporation of Pennsylvania Filed Feb. 24, 1967, Ser. No. 618,466 Int. Cl. B65b 21/02 US. Cl. 214-317 27 Claims ABSTRACT OF THE DISCLOSURE The disclosure involves a highly maneuverable load carrier, typically a multi-wheeled trailer for carrying a container, well adapted for transporting and dumping a pot of molten slag, and it includes many features of construction and operation, such as: a frame configured to provide ample clearance for pick-up and dumping of slag pots; pivoted lifting arms for raising, dumping and lowering a slag pot; adjustable hooks to assist in tipping a pot for mechanism for knocking a tilted container against an abutment, to dislodge material; pressure sensing stabilizing feet to carry part of the load when dumping; power devices for operating the arms, the hooks and the stabilizers; controllable hydraulic system for powering and coordinating various of the foregoing parts and their functions; and mechanism for effecting transverse and longitudinal equalization of the load on the various supporting wheels of the load carrier.

This invention relates to container carriers, and while it is generally useful for the lifting, transporting and unloading of heavy objects, and also for handling, transporting and emptying of loaded containers, it is particularly adapted to the handling of Waste buckets, ladles, cinder containers, and slag pots. In the steel industry, especially, the problem of removing molten slag from the plant and transporting it to a suitable dump and there disposing of it is a very substantial problem, and the equipment of the present invention is very well adapted for that and similar purposes. In short, it is quite versatile for the lifting, handling, transporting and dumping of containers of heavy and hazardous materials, for the emptying out of materials which tend to stick in the container, and for the return of the emptied containers to the point of origin.

One of the primary purposes of the invention is to assure the safe, rapid and efficient transport and dumping of heavy harmful materials, and more particularly to do so by the provision of a highly maneuverable, versatile container carrier, especially a carrier which can be readily coupled to and uncoupled from a tractor of one or more known types, and which can be operated, in the steps of picking up a container, transporting it, dumping the load, dislodging materials which tend to stick, and again transporting and returning the container, all by means of controls which are readily operable by the person handling the tractor.

While it has been known in the art to provide carriers for lifting a container such as a slag pot from a car or platform, for example, and for moving and dumping the same these have not been wholly successful in certain respects, for example in connection with the lifting of such loads, especially slag pots, directly from the ground level or the floor on which the vehicle is operating, nor with respect to the emptying out of materials tending to adhere to the pot, commonly called stickers in the art. Neither have such carriers heretofore had the facility nor the safety characteristics of the carrier of the present invention, nor have they generally been so maneuverable; and their structure has often been cumbersome, expensive, and difficult to operate and maintain.

The present invention thus contemplates the obviation of such disadvantages and drawbacks of the prior art, and in general contemplates the provision of an improved container carrier, novel and advantageous as to both structure and function, and having improved operating mechanism and characteristics, especially a hydraulic control system having coordinated and cooperating mechanisms for raising, shifting and lowering a slag pot or the like; for shifting, tilting, and dumping the container; for giving the container an impact or thumping operation in order to empty out sticking material; for stabilizing the equipment during all these operations; for quickly and safely returning the container to its position on the carrier and thereafter transporting the container and unloading it upon the ground or other suitable location.

In connection with the foregoing, the invention contemplates the provision of a container carrier which at its front end is adapted to cooperate with any suitable tractor, and at its rear-end is adapted to pick up, handle, discharge, and set down the container, and to do this in such a way that the framework, running gear and operating mechanisms of the carrier do not interfere in any way with the necessary clearance space for the container; and further in such manner that in lifting the container, particularly when fully loaded, the weight thereof is carried in substantial part by stabilizing means in engagement with the floor or ground during lifting, dumping, thumping and setting down of the container, whereas, during transportation of the container (loaded or empty) the weight thereof is carried further forward on the carrier, and more specially at a point which places some of the load thereof upon the tractor.

Additionally, the invention contemplates a control system for the mechanism on the carrier, and more especially a hydraulic control system, having built-in safety characteristics, especially such as will assure that the stabilizing means will make firm contact with the supporting surface, irrespective of irregularities therein; that those operations of the equipment which are best carried out by mechanisms having relatively small capacity and/or requiring relatively low hydraulic pressures are so coordinated with those parts of the equipment which require greater power and/ or higher pressures that the higher powered mechanism, notably that for lifting and shifting and thumping the container cannot be operated to raise the container until after the lower powered mechanisms have properly functioned.

Still further, the invention contemplates a carrier having the combination of great load carrying capacity and high maneuverability; and in the preferred embodiment this is provided by employing multi-wheeled running gear assemblies, utilizing large pneumatic tires, each assembly preferably having four wheels and being equalized both laterally and longitudinally, and by providing a pivotal mounting at one end of the carrier for cooperation with a tractor of short turning radius, and further by providing mechanism for guiding and retaining the equalizer structures in their proper positions regardless of the shortness of turn of the equipment.

More specifically, the invention contemplates a container carrier having a frame with a central cross-structure providing a carrying deck or platform for a container such as a slag pot, and with longitudinal side structures extending rearwardly therefrom, the frame being configured to provide clearance for the container, preferably by being formed as an open U viewed in plan, together with equalized multi-wheeled running gear assemblies extending beneath the side structures and receiving weight from the frame; the carrier further being provided with boom arms, one at each side, independently pivoted on the frame for swinging movement in longitudinal vertical planes between generally horizontal rearward positions,

and generally higher forward positions with means on said arms for engaging a pair of lifting lugs, one at each side of the container; and further having power mechanism for moving said arms between the said rearward and forward positions and incorporating means for coordinating the independent pivotal movement of said arms, whereby a container may be picked up at the rear of the carrier and swung up to a transport position upon said cross-structure; the carrier further having power actuated retention hooks, pivotally mounted on said side structures, to the rear of said boom arms, for movenment in longitudinal vertical planes from generally horizontal rearward positions to upwardly inclined positions for engagement with a pair of dumping lugs or trunnions, one on each side of the container, whereby a loaded container when swung backward by the boom arms is caused to tilt over, engage dumping cams, and dump rearwardly in a position between said longitudinal side structures; and further comprising vertically adjustable stabilizer feet, one at the rear end of each side structure, having pressure sensing power means for urging said feet against a surface beneath the carrier, during lifting, dumping and thumping operations of the mechanism; and having guiding means for said stabilizers and guiding means for equalizer mechanism of said running gear assemblies, together with unified supports for said guiding means, and transverse frame bracing in a location between said assemblies at the forward part of the horizontal U shaped frame structure.

The invention additionally involves the coordination or synchronizing of the operation of the boom arms on the two sides of the machine, of the retention hooks on the two sides, and of the stablizer feet on the two sides, and also the coordination of the boom arms, the retention hooks and the stabilizer feet relative to each other, through the controlled operation of hydraulic units powering these devices; all in a manner more fully brought out hereinafter.

In its preferred embodiment, the invention is described and illustrated herein with reference to a carrier for handling slag pots or the like, but it will be understood that this is by way of illustration and not by way of limitation.

FIGURE 1 is a side elevation of a mobile molten slag transporter, constructed in accordance with the invention, for picking up and carrying a slag pot as shown, and adapted also for dumping the contents of the slag pot and for depositing the slag pot on the ground or floor at a desired location;

FIGURE 2 is a plan view of FIGURE 1 including a portion of a towing tractor;

FIGURE 3 is a somewhat enlarged one half end view of FIGURE 1 as viewed from the right of that figure;

FIGURE 4 is an enlarged detail view of a stabilizer assembly employed in the equipment, showing the raised position of the foot in full lines and a typical lowered position in chain dotted lines;

FIGURE 5 is a plan section taken as indicated by the line 55 on FIGURE 4;

FIGURE 6 is an enlarged plan view of one of the running gear assemblies shown in FIGURES 1 and 2;

FIGURE 7 is a sectional elevational view of FIGURE 6 taken as indicated by the line 7-7 on FIGURE 6;

FIGURE 8 is a cross section taken as indicated by the line 8-8 on FIGURE 1 with a portion of the view broken out to condense the figure;

FIGURE 9 is a cross section taken as indicated by the line 99 on FIGURE 1;

FIGURE 10 is a more or less diagrammatic view illustrating the slag pot in various positions during the raising of it from the floor or from the ground onto the carrier;

FIGURE 11 is a view similar to FIGURE 10 illustrating the slag pot in various positions of a dumping cycle;

FIGURE 12 is a diagram showing the hydraulic system for controlling and powering the various mechanisms or devices of the equipment.

The mobile equipment of the illustrative embodiment of the present invention comprises in general a frame F, running gear RG, boom arms B, B, retention hooks R, R, tilting or dumping cams C, C, equalizers or walking beam structure W, W, associated with the frame and running gear, stabilizer mechanisms S, S, and a slag pot or container SP for slag or other material being handled.

The frame F comprises a central cross-structure and longitudinal side-structures extending rearwardly therefrom, thus forming an open U, viewed in plan, as is readily seen in FIGURE 2. This frame includes suitable longitudinal members 20 and transverse members 21 rigidly secured together to form a rugged heavy duty framework and includes a support plate or platform 22 on which the slag pot SP is supported when in its transport position as shown in FIGURE 1.

As shown in FIGURE 2 the rearwardly extending side structures 23, 23 of the frame have a clear space 24 between them so as to provide clearance for the slag pot as it is raised and lowered, also when dumped, in a manner hereinafter appearing. In this regard, the frame structure, the boom arms B, B, and the laterally located running-gear assemblies, all cooperate in providing adequate clearance for the handling of the slag pot. Furthermore, since the boom arms B, B, are individually pivoted, and have no direct mechanical cross-connection from pivot to pivot, there is nothing to prevent them and their pivots 30, 30 from being located in the most advantageous positions, both vertically and horizontally. For example, it is possible to locate the main pivot pins 30, 30 of the boom arms B, B, at such positions with respect to the running-gear RG and stabilizers S as to obtain the most advantageous weight distribution both for transport and for conditions of dumping, and this without having slag pot interference with frame structure.

The running gear RG consists of one multi-wheeled unit or assembly 31 at each side of the carrier. Each such assembly comprises an equalizer or walking beam structure W having a pair of longitudinal beam members 33, 33, spaced apart by cross plates 34, 34, secured thereto as by welding and each having a centrally located pivot sleeve 35 containing a bearing bushing 36 (FIG. 8). The beam members 33 are strengthened by webs at 37 and 38.

Longitudinally spaced bearing blocks 39, 39 (FIG. 7) are secured as by means of bolts 40 to the cross plates 34 and are provided with bearing bushings 41, 41, for the longitudinally-extending pivot shafts 42.

Between the bearing blocks 39, 39, transverse brackets 43 are secured to the pivot shafts 42 and these brackets are provided with support members 44 and 45 in which spindles 46, 46, for the wheels 47, 47, are secured. Thus each pair of wheels is mounted for free transverse rocking movement in the bearing blocks 39, 39 of the walking beam structure.

Referring particularly to FIG. 8 the two equalizers or walking beam structures are pivotally mounted, by means of the pivot sleeves 35 of the walking beams on transverse axles 50, secured by bolts 51 in sleeves 52 of brackets 53, 53, which are secured as by means of welding at 54 to the side members 55, 55, of the frame F. The axles 50, 50, are secured to a transverse spreader beam or tube 56 by means of bolts 57. End caps 58 providing shoulders 59 are secured to the ends of the axles 50. Thus, in effect the axles and spreader beam constitute a tie member, rigidly supported from the frame F, for the equalizer walking beam structures, preventing them from spreading and maintaining them in alignment, it being pointed out that these structures are trunnioned on the axle portions of the rigid tie member by means of the bushed bearing sleeves 35, 35.

The longitudinal beam members 33, 33, of the equalizer structures extend well beyond the locations of the wheel spindles and at their end portions 33a (FIGS. 5, 6, 7, and 9) they are guided in guide brackets 60 and 61 secured to the frame side members 55 as by welding indicated at 62 in FIGURE 9 and located between the beam members 33, 33. The guide brackets 60 and 61 are provided at their side faces with wear plates 63 of wear resistant material for the beam members 33, 33, as clearly seen in FIG. 9.

The guiding of the end portions of the equalizing walking beam structures is very advantageous in that it prevents distortion and damage thereto under lateral swinging of the trailer (or rig as it is sometimes called) when the towing tractor 70 (FIGS. 1 and 2) turns sharply to the right or left on the tractor hitch 71 as indicated in dot-and-dash lines in FIGURE 2. In this regard, the rugged tie member between the two running-gear assemblies at the two sides of the rig cooperate with the end guides 60 and 61 in maintaining proper alignment of the equalizer walking beams and preventing distortion of them.

Referring now to the stabilizer mechanism S it will be seen from FIGURE 2 that there is one such mechanism at the rear end of each of the rearwardly extending side structures 23 of the frame F. Each of these stabilizer mechanisms (FIGS. 1-5) includes a stabilizer foot 75, an operating piston and cylinder device 76 and stabilizer guide arms 77.

The piston and cylinder device 76 is pivotally mounted at 78 in a bracket 79 of a housing 80 secured to the end of the frame side structure 23. The stabilizer foot 75 is pivotally mounted by means of a shank member 81 and pin 82 in the guide arms 77 which are pivotally mounted at 83 in the rear equalizer guide bracket 61. The clevis 84 of the piston rod 85 is connected to the guide arms 77 by means of the pin 82. Thus, the bracket structures 61 serve a double function.

The shank member 81 has a shouldered bottom portion 86 with a semi-spherical lower surface 87, and the foot 75 has a semi-spherical cavity 88 and a retaining collar 89 adapted to seat on the shouldered portion of the shank member 81 when the stabilizer is raised off the ground or floor so that the foot hangs freely from the shank member as best seen in FIGURE 4.

When the piston and cylinder device 76 is actuated to move the foot to stabilizing position the spherical surfaces 87 and 88 mate and the foot accommodates itself to the ground as shown in dot-and-dash lines in FIGURE 4. Contact of the foot with the ground is established by pressure sensing rather than by position sensing to ensure load stabilization regardless of ground irregularities as will fully appear hereinafter.

Reverting now to the boom arms, it will be seen that each boom arm B is independently pivotally mounted, by means of a pin 30 above referred to, in a bearing block 100 bolted to the side structure 23 of the main frame F and is provided with a specially shaped hook-like portion 101 at its free end and a lug 102 for pin connection at 103 to the piston of a piston and cylinder device 104, which is trunnioned at 105 in bearing blocks 106, 106, secured on the main frame F.

The two boom arms B, B, are structurally independent but are functionally synchronized or coordinated by the hydraulic control of the piston and cylinder devices as will fully appear hereinafter.

The slag pot SP is provided at its sides and adjacent its top wtih lifting lugs or trunnions 107, 107, which cooperate with the hook-like portions 101 of the boom arms in the raising and lowering of the slag pot.

The bearing blocks 100 are so located on the frame and the length of the boom arms is such that when the boom arms are in the raised position of FIGURE 1 the slag pot will rest on the platform or supporting plate 22 of the main frame so that the plate takes the load of the slag pot and relieves the hydraulic system during transport. It is to be observed that in this position the slag pot is quite close to being vertically above the front wheels of the wheel assemblies, although it is preferably a little forward of that location so as to throw some additional weight onto the tractor during transport.

Referring particularly to FIGURE 10, at the extreme rearward or down position of the boom arms, i.e., position I, the hooks thereof are in a position below the lifting lugs 107 of the slag pot so as to clear them when the rig is backed toward or towed away from a slag pot SP resting on the ground or floor.

In order to lift the slag pot from the floor and to deposit it on the support plate or platform 22 of the rig the hydraulic piston and cylinder devices 104 are actuated, under a low-pressure mode of operation, and the boom arms first arrive at a position 11 in which the hook portions 101 just engage the lifting lugs 107 of the slag pot. The rig may then be backed a little further until the lugs seat in the hook portions 10112. Thereafter, under the highpressure mode of operation, the slag pot is raised to the suspended upright position as indicated at III and continues past that position, and finally the boom arms arrive at position IV in which the slag pot rests on the platform 22 of the rig.

It is to be noted that in this operation the retention hooks R (the function of which will be later described) are retracted to a down or idle position so that the dumping or tipping lugs 110, provided at the sides of the slag pot toward its bottom for cooperation with the retention hooks, as will hereinafter appear, will clear those hooks as the bucket is raised. Also these dumping lugs 110 will clear the tilting cams to be described later.

The procedure just described is followed, for example, when it is desired to transport a loaded slag pot from the floor of a mill to a location where it is to be dumped. It is also pointed out that if it is desired only to transport the slag pot from place to place at the mill it can be deposited from the rig onto the floor by reversing the above procedure.

It should be noted that both the raised and lowered positions of the stabilizer S are indicated in FIGURE 10. They are raised when the rig is being maneuvered, for example until lugs 107 are seated at 1011: in hooks 101, when a slag pot is about to be lifted, and likewise after a slag pot has been set down on the ground. They are also raised when the rig is travelling (with the slag pot in position IV). But they are lowered and held against the floor or ground, by dydraulic pressure, when the pot is being swung on arms B, B (as at positions II and IP) and during the dumping and thumping operations (indicated at positions V through IX in FIGURE 11). These operations of the stabilizer S are coordinated with the operation of the boom arms B, B, and of the retention hooks R, as later described with reference to the controllable hydraulic system illustrated in FIGURE 12.

It is pointed out that when the slag pot arrives at the intermediate position shown in broken lines at IP its gravity is overcentered, both in loading a slag pot onto the rig or in unloading it from the rig, so that an overhauling load condition results. The manner in which this is counterbalanced will appear hereinafter in connection with the description of the hydraulic control system.

Referring now to the functioning of the rig for slag dumping, the rig, with a loaded slag pot resting on the platform 22, and with the retention hooks R in lowered or retracted position all as shown in FIG. 1, is backed against a dumping wall and the stabilizer piston and cylinder devices 76, 76 are actuated to lower the feet 75 into pressure contact with the land 116 of the dumping wall, as shown in FIG. 11.

Before proceeding with the dumping operations it is noted that, as shown in FIGS. 2 and 3, there are two retention hooks R, R, each pivoted at 117 in a bracket 118 secured on the frame at each side structure 23. The retention hooks are actuated by piston and cylinder devices 119, 119, and are so located on the frame as to register and cooperate, when actuated, with the side dumping lugs 110, 110, of the slag pot (FIG. 3).

Outboard of and in lateral spaced relation to each retention hook a tilting or dumping cam C is mounted on each side frame structure 23. These cams also are located to register and cooperate with the side dumping lugs of the slag pot in dumping operations as Will now appear.

After having backed the rig to the position just described and shown in FIG. 11, the piston and cylinder devices 119 are actuated to swing the retention hooks counterclockwise from the position shown in FIGS. 1 and 10, and the boom piston and cylinder devices 104 are actuated to swing the boom a-rms B, B, clockwise until the lower or dumping lugs 110 of the suspended slag pot engage the shanks of the retention hooks as shown in the broken line position V of FIG. 11.

As the boom arms continue in their clockwise or down movement the dumping lugs fully seat in the retention hooks as shown in the full line position VI.

Upon further movement of the boom arms the slag pot starts to tilt by virtue of the hooked engagement with the retention hooks and when it reaches the broken line position VII the dumping lugs engage the tilting or dumping cams C and final tilting movement of the slag pot takes place until it reaches a full dump position for discharging the load of slag, in which position the lip 120 of the slag pot engages the land 121 of the dumping wall structure 115 as shown in broken line position VIII in FIG. 11. It is pointed out that in this final movement the engagement of the dumping lugs with the inclined tilt or final dumping cams C relieves the retention hooks of a major part of the dumping load.

In instances where all of the slag does not discharge fully out of the slag pot, i.e., if there is what is known as a sticker in the slag pot, the operator actuates the boom piston and cylinder devices 104 to raise the slag pot a distance, as indicated at IX in FIG. 11, perhaps 3 or 4 feet, more or less determined by the nature of the sticker and by experience, and then he actuates a quick release boom drop valve, later described, which drops the boom arms and slag pot by gravity until the lip 120 strikes the land 121 with a thump to forcibly discharge the sticker.

Referring now to the hydraulic diagram of FIGURE 12, the hydraulic control system, for the boom arm cylinders 104, the stabilizer cylinders 76, and the tilting cylinders 11-9, above described, comprises in general a boom control valve 125, a stabilizer control valve 126, a tilt control valve 127, a source of fluid pressure including a power driven fluid pump 128, a reservoir 129, and a pilot operated relief valve 130, set, for example, at 2500 p.s.i., a synchronizer or flow divider 131 for the boom arms including a pair of reversible fluid motors 132, 132, coupled together at 134, and a boom drop valve 135.

It is pointed out that the various valves of the hydraulic circuit are known types of valves, commercially available, and therefore are only diagrammatically indicated in the drawing (FIG. 12).

The stabilizer cylinders 76, 76 are connected at their lower ends by line 140 and at their upper ends by line 141 provided with pilot operated check valves 142 and 143 and with accumulators 144 and 145.

A line 146 connects line 141 to a sequence valve 147 having a by-pass check, which sequence valve in turn is connected by line 148 to a pilot operated valve 149. The valve 149 is connected by line 150 to the pilot operated relief valve 130 and by line 151 to a pilot relief valve 152 set, for example, at 500 p.s.i.

A line 153 connects the line 141 to a pressure reducing valve 154 having a by-pass check, and a line 155 connects valve 154 to stabilizer control valve 126. A line 156 connects control valve 126 to the line 140 of the stabilizer cylinders 76, 76.

The boom cylinders 104, 104, are connected at their lower ends of the fluid motors 132, 132, by way of lines 160, 160, in which counterbalance values 161, 161, with pilo over-ride are located; and a line 162 having a pilot operated valve 163 interconnects the lines 160, 160. A line a connects the fluid motors 132, 132, to the boom control valve 125. The upper ends of the boom cylinders are interconnected by a line 164 in which counterbalance valves 165, 165, with pilot over-ride, are located; and line 164 is connected to the boom control valve by line 166. The tops and bottoms of the boom cylinders 104, 104, are interconnected by lines 167, 167, in which pilot operated check valves 168, 168, and check valves 169, 169, are located.

The counterbalance valves 161, 161, and 165, 165, are set to open at 1.3 times the maximum over-center load condition of the boom arms in either their direction of loading or unloading. The pilot over-ride reduces the 1.3 setting of the valves so that smooth and positive control is afforded during normal operation of the boom arms. In the event of any fluid-pressure failure, the counterbalance valves automatically close, preventing movemens of the boom arms, which is an important safety feature.

In order to provide for a quick drop of the boom arms to remove stickers," above-mentioned, from the slag pot, a boom drop valve 135 is provided and is connected in the circuit by lines 170, 171 and 172.

The tilt or retention hook cylinders 119, 119, are interconnected at their lower ends by line 173 and at their upper ends by line 180. Line 173 is connected to the control valve 127 by line 174 in which are located a pressure reducer 175 with a by-pass check valve, and a flow control valve 176. Line is connected to the control valve 127 by line 177 in which a flow control valve 178 i located. Pressure accumulators 179, 179, are provided in the line 173.

Assuming now that a loaded slag pot is resting on the floor and that it is desired to transport it to another point for unloading, then the rig is backed toward the slag pot, and maneuvered by the operator until the hook portions of the boom arms are under and in vertical alignment with the lifting lugs of the slag pot as shown in position I of FIGURE 10..

It is pointed out that for this operation the boom control valve 125 was actuated to move the boom arms to their down position, the stabilizer control valve 129 was actuated to retract the stabilizer feet to their upper free hanging position and the tilt or retention hook control Nalve 127 was actuated to retract the retention hooks R to their down or inactive position.

To move the boom arms to their down position pressure fluid is led from the boom control valve 125 to the boom cylinders-by line 160a, fluid motors 132, 132, and by lines 160, 160, leading from the fluid motors to the boom lowering ends of the boom cylinders.

To raise the stabilizer feet 75 to their up or free hanging position pressure fluid is led from the stabilizer control valve 126 to the foot raising ends of the stabilizer cylinders by lines S 156 and 140.

To retract the retention hooks R to their inactive positions, pressure fluid is led from the tilt control valve 127 to the retracting ends of cylinders 119 by supply lines 177 and 180.

With the rig in the aligned position mentioned, the boom control valve 125 is moved to its detent position. In this detent position of the boom control valve 125 pressure fluid is led to the boom raising ends of the boom cylinders 104 by means of supply line 166, to raise the boom arms B until their hook portions 101 are in positive engagement with the lifting trunnions 107 of the slag pot. This is the position marked II in FIG. 10. It is pointed out that since the stabilizer feet are then in their up or free hanging position (which is the full-line position shown in FIG. 4) the system is in low pressure mode of operation, e.g. 500 p.s.i., which is insuflicient to lift the slag pot off of the floor. This prevents unintentional lift of the slag pot at this time. Were such lifting to occur, when the stabilizer feet 75 are off the ground, damage or upsetting of the equipment could result.

With low pressure still tending toward raising the boom arms B, the rig may now be backed up a little farther until each lifting trunnion 107 is seated in the base 11% of the cooperating hook 101.

Next the stabilizer control valve 126 is actuated to lower the stabilizer feet into pressure contact with the floor. This floor contact is established by pressure sensing rather than by position sensing, thus ensuring load stabilization under varying floor or ground conditions. Once the stabilizers have established their position by pressure, the low pressure mode 500 p.s.i. is thrown into high pressure mode, eg 2500 p.s.i., which enables the slag pot to be lifted under control of the boom control valve 125.

In order to throw the system into this high pressure mode a pilot operated valve 149 is associated with the relief valves 130 and 152.

In this position of the stabilizer control valve pressure fluid is led from the valve 126 to the foot lowering ends of the stabilizer cylinders 76, 76, by line 155.

With the stabilizer feet in this pressure contact with the floor and with the consequent establishing of a high pressure mode, and with the boom control valve 125 sup plying high pressure to the boom raising ends of the boom cylinders, the boom arms will raise the loaded slag pot and deposit it on the support plate or platform of the rig. Then the stabilizer control valve 126 is actuated to raise the stabilizer feet and the slag pot is transported to a designated dumping area.

To accomplish dumping of the slag pot load the rig is backed against an abutment 115 as shown in FIGURE 11, and the stabilizer control valve 126 is actuated to lower the stabilizer feet into pressure ground contact in the manner above described. Next the tilt control valve '127 is actuated to raise the retention hooks R into contact with the tilting lugs 110 of the slag pot. To accomplish this, pressure fluid is led from the tilt cylinder control valve 127 to the hook raising ends of the tilt cylinders 119 by lines 174 and 173.

Next the boom control valve 125 is actuated to raise the slag pot off the supporting platform and to lower it to its dumping position. In this lowering movement the tilting lugs 110 of the slag pot seat in the retention hooks R (as shown at positions V and VI) and finally engage the tilting cams C (as seen at position VII) thus causing the slag pot to rock or tilt on its main trunnions 107, in the hooks 101 of the boom arms B, and finally to arrive at its fully tilted or dumping position, designated VIII.

In the event that some slag sticks in the slag pot, commonly known in this art as a sticker, the operator actuates the boom control valve 125 to raise the boom arms and, when the slag pot has been raised to the point where its edge or lip is approximately 3 to 4 ft. above the dump wall, the boom drop valve 135 is actuated to cause the slag pot to drop with a thump against the dump wall, e.g., with lip 120 against land 121. This operation is repeated until the sticker or stickers are =finally dislodged. The drop valve 135 is located in the lines 171 and 172 of the boom control system.

Next the operator raises the boom arms and deposits the empty bucket onto the supporting platform of the rig thus completing a cycle of operation.

When, in the movement of the boom arms, the slag pot arrives at a position where its gravity is overcentered in the direction of loading or unloading, an overhauling load condition takes place, and, in order to control this, counter-balance valves 16-1 and 165, set at 1.3 times the maximum overhauling load condition, are provided in the boom cylinder lines 160, 160 and 164.

From the foregoing description, many practical advantages of the invention will now be apparent, and a few of them are here mentioned. For example, the arrangement of the framing of the carrier, together with the disposition of the running gear assemblies make it possible to utilize a relatively simple mechanism for lifting the slag pot all the way from floor level right up to the carrying platform, in which position a part of the load is imposed upon the tractor. By employing a separately pivoted boom arm at each side of the carrier, with no cross structure between the pivoted ends of said arms, and by synchronizing the two arms through the controlled power devices herein described, it is possible to locate the boom arm foot pivots most advantageously, both as to vertical position and as to longitudinal position, so as to obtain the most advantageous disposition of the load, not only for the transport condition (as in FIGURE 1) but also for the lifting, dumping and thumping conditions (as in FIGURES 10' and 11).

The shifting of loads and shocks, during dumping and thumping, from the retention hooks to the cams, enables the hooks and their actuating mechanism to be of relatively light construction, and also tends to reduce wear and damage generally.

The running gear system disclosed herein facilitates the use of pneumatically-tired wheels, as shown, which is of substantial advantage in the operation of the equipment over all kinds of rough terrain as twel las on mill floors and the like.

While the fluid-pressure system, preferably hydraulic, is shown in diagrammatic form as one unified system, and indeed all of it, including the pump, reservoir, manual controls and other parts, could be mounted on the trailer itself (along with the power cylinders which move the boom arms, the retention hooks and the stabilizers), it will be understood that the preferred arrangement is one in which at least the pump, reservoir and controls are mounted on the tractor 70, and are connected by flexible hydraulic conduits with those parts of the system which are herein shown as being on the trailer.

I claim:

1. A container carrier comprising a frame with cross structure and longitudinal side-structures extending rearwardly therefrom in positions to leave a clearance space between them and extending free and clear above them so as to accommodate a container being arcuately moved onto the carrier or tipped for dumping; running-gear assemblies at the sides of the frame and receiving weight therefrom; boom arms, having free ends extending separately at the respective sides of the carrier, and pivoted thereon for arcuate swinging movement in longitudinal vertical planes between generally horizontal rearward positions and generally higher forward positions; independent means adjacent the free ends of the two arms for respectively engaging a container at the sides of the latter so that the container itself and the cross-structure of the frame constitute the major transverse interconnection between said boom arms during operation thereof; and power mechanism for moving said arms in synchronism between said rearward and forward positions, whereby a container may be picked up from ground level at the rear of the carrier and swung up to a transport position over said cross-structure, and may also be dumped, without interference from the frame or the running-gear assemblies.

2. The carrier of claim 1, wherein the boom arms are structurally independent and independently pivoted, and said power mechanism includes equalizing means to coordinate their movements.

3. The carrier of claim 1, wherein said power mechanism embodies a fluid pressure system acting to move said arms both fore and aft of an overcenter position and includes automatic means for balancing the overhauling load.

4. The carrier of claim 1, with movable surfaceengageable stabilizers, fluid motor means for moving the boom arms, fluid motor means for moving said stabilizers, means for delivering fluid under a relatively low pressure to both said motor means, in sequence, and means for delivering fluid under a relatively high pressure to said 1 1 motor means for the boom arms only when said stabilizers are in surface-engagement. I

5. The carrier of claim 1 with movable surfaceengageable stabilizers, one at each side, and pressuresensing power means for moving them both into surfaceengagement regardless of differences in surface level at the two sides.

6. The carrier of claim 1 wherein said power mechanism embodies a fluid-pressure system actuable to move said arms, container tipping mechanism movable between operative and inoperative positions, and fluid-pressure means for actuating said tipping mechanism to operative or inoperative positions actuable independently of the actuation of the fluid pressure system for said arms.

7. The carrier of claim 1 with mechanism for engaging the container to initiate tilting thereof during operation of said arms, for a dumping operation, power means for actuating said arms for effecting dumping of the container, and means for causing a sudden drop of said container in tilted position whereby to knock out sticking material.

8. The carrier of claim 7, with cam means positioned to engage the container and relieve said mechanism of shock incident to such knocking action.

9. The carrier of claim 7, with stabilizer means engageable with a fixed surface to take load and shock during dumping and knocking operations.

10. The carrier of claim 1 with movable surfaceengageable stabilizers having power mechanism, movable means adapted to cooperate with the container in effecting the dumping thereof and having power mechanism, and a control system for coordinating the three power mechanisms.

11. A container carrier comprising a frame with crossstructure and longitudinal side-structures extending rearwardly therefrom to form an open U viewed in plan; running-gear assemblies at the sides of the frame and receiving weight therefrom; boom arms at the respective sides of the carrier independently pivoted thereon for swinging movement in longitudinal vertical planes between generally horizontal rearward positions and generally higher forward positions; means on said arms for engaging a container adjacent the sides thereof; and power mechanism for moving said arms between said rearward and forward positions and incorporating means for coordinating the independent pivotal movement of said arms, whereby a container may be picked up at the rear of the carrier and swung up to a transport position over said cross-structure.

12. The carrier of claim 11 wherein said runnin -gear assemblies are multiple-wheeled, each with a longitudinal equalizer extending from the region of said cross-structure rearwardly adjacent the rearward extensions of said sidestructures, and having vertical guideways for the ends of the equalizer fixed on the frame at the forward ends of the equalizer and fixed on the rearward extensions of the side-structures at the rearward ends of the equalizers.

13. The carrier of claim 12, having vertically-movable surface-engaging stabilizers at the rear ends of said side-structures.

14. The carrier of claim in common as support means for the rear vertical guideways.

15. The carrier of claim 12 wherein the frame has supports at the sides and the equalizers have pivotal mountings in said supports at locations between the foreand-aft wheels.

16. The carrier of between said supports.

13, having brackets serving for said stabilizers and claim 15 with rigid cross-bracing 17. The carrier of claim 15 wherein the equalizers carry pivots disposed longitudinally, at locations foreand-aft of said pivotal mountings, and the wheels are disposed in fore-and-aft pairs, each pair being independently rockable about one of said longitudinal pivots.

18. The carrier of claim 13 with power mechanism for lowering said stabilizers into contact with a surface including means substantially equalizing the contact pressure of the stabilizers at both sides regardless of differences in travel of the stabilizers required to make surface contact.

19. The carrier of claim 13 with means coordinating the container-lifting operation of said power mechanism for the boom arms and the operation of said stabilizers.

20. The carrier of claim 11 in whch the means of engagement with the container provides a pivot at a predetermined transverse axis relative thereto, and the carrier also has retention means adapted to engege such container at a point below the axis of engagement therewith of said boom arms, whereby, when said arms move the container rearwardly it is tipped for dumping, and the open U provided by said frame allows clearance for the container during the dumping operation.

21. The carrier of claim 20 wherein said retention means comprises a movable hook device.

22. The carrier of claim 20 wherein said retention means comprises a weight-bearing cam device.

23. The carrier of claim 20 wherein the boom arms have hooks for engaging lifting trunnions at the sides of a container and wherein said retention means comprises a pair of pivoted hook devices operable, alternatively, to engage tilting lugs on a container at each side thereof beneath the lifting trunions for a dumping operation or to clear said lugs for a loading or unloading operation.

24. The carrier of claim 23 wherein the retention means further comprises a pair of weight-bearing cam de vices positioned to engage said lugs in the concluding part of a dumping operation.

25. In a slag transporter, a mobile chassis having a tractor hitch neck at its forward end, pressure fluid acuated stabilizer feet at its rear end, and running-gear assemblies intermediate said ends, boom arm pivotally mounted on said chassis intermediate of said ends, presure fluid mean for rocking said boom arms from an upright position to a rearward down position, a slag pot cradled in said boom arms in upright position to retain slag therein when said boom arms are in upright position, and tilting means engageable by said slag pot upon movement of the broom arms to said rearward down position to titlt the slag pot into slag dumping position.

26. The slag transporter of claim 25 wherein the slag pot has upper trunnions and the boom arms have hooks engageable therewith, and the pot further has lower trunnions and the tilting means comprise hooks engageable therewith.

27. A slag transporter according to claim 25, wherein the frame has a cross-structure and the slag pot when seated on the carrier rests upon the cross-structure of the frame, in a position in advance of the longitudinal center of the running-gear assemblies so that weight from said slag pot is imposed upon the tractor through said neck.

References Cited UNITED STATES PATENTS 2,672,247 3/1954 Jewett 214-314 3,200,975 8/1965 Chase 214-317 3,330,429 7/1967 Kress 214-314 HUGO O. SCHULZ, Primary Examiner.

UNITED STATES PATENT OFFICE 56 CERTIFICATE OF CORRECTION Patent No. 3 446 78 Dated May ZL 1969 Inventor(s) Richard A N1 1181 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 6, line. 45 "dydrau'lic" shouldiho hydraulic-- Co]. 8 )i'ng 19 "m w-Hews" slmuhi he --wovemcnt- CD1 9 I ine .3 '1 10b" 11m: 1 ha 1 U H) Col. 10, line 22 we! 135" should he -wel! :15"

C01. 12., line. 15 "whch" slmuld be which C01. 12, line 18 "engage." hould he engage-- C01. 12,, line 49 "hrunm" should be "boom SIGNED AND SEALED MAR 2 4 1970 Q Attem- Edwnrd H. Fiamhm In M: M" n WILLIAM E. SOHUYLER, JR. L'Mc mg w Commissioner of PatantgJ 

